Originally Posted by F34Me?

I would ditch the bolt and use a rather thick bar through the hollow axle. The axle is shaped in such a way that one side is held on by the counterforce from the other side. The pinch bolts are mostly just meant to keep the axle from spinning, they only have 20lb of torque I think?

My idea was to use a rather thick hollow rod which is the same OD as the bolt that goes into the axle. Use a collar on the other side to hold it straight and recess the slider into that side so it isn't sticking out further. Then bolt the slider onto the other side to replace the bolt that you removed. Of course you'd have to do a fair bit of searching to find sliders that would be capable of meeting all these criteria.